1. Field of the Invention
This invention relates to sectional doors and, more particularly, to a novel tongue for the joint between door sections for minimizing water dripping from the joints as the sectional door is raised to its overhead, open position.
2. The Prior Art
Sectional doors are the closure of choice for large openings such as those found in garages, warehouses, storage sheds and the like. The sectional door is the preferred closure system for these types of openings since they are too wide for a conventional, hinge-mounted door. Specifically, a hinge-mounted door of these dimensions would require extremely robust hinges while the door itself would demand sufficient space in which to pivotally swing between the open and closed positions. As such, the sectional door has numerous advantages in that it provides a vertical closure that is strong, decorative, and yet stores out of the way in its elevated, open position.
A sectional door is fabricated from two or more elongated door sections. The length of the door sections is preselected in order to completely span the opening in which the sectional door is mounted. Each door section is placed with its plane oriented vertically. The door sections are hingedly mounted serially to the adjacent door section. The two opposite edges of the sectional door are movably mounted in a pair of support tracks, one on each side of the opening. Each track has a vertical component which supports the sectional door in its vertical, closure position across the opening. Each track also has a horizontal component which is secured at an elevated position above the opening. A curved section of track connects the vertical component with the horizontal component. The hinge mounting between door sections allows the sectional door to traverse the curved portion of the track between the open and closed positions. It is this traversal of the sectional door across the curved section of track that necessitates that the sectional door be constructed from individual door sections joined together by hinges in the foregoing edge-to-edge relationship.
The placement of the door sections in this edge-to-edge relationship creates a number of unique problems dealing not only with their overall alignment but also the weather resistance and safety of the sectional door. I developed a tongue and groove system for my steel sectional doors a number of years ago in order to assure that the sectional door retained a planar orientation when the sectional door was lowered to its vertical, closed position. Others have recognized the value of this feature and have freely copied my sectional doors. The tongue and groove system I adopted was also intended to improve the weather resistance of my sectional doors. Previously, the abutting edges of the door sections were flat so that a certain amount of wind could pass through the cracks. Also, any wind driven rain or spray could enter the garage through the cracks.
While my tongue and groove system did solve most of the problems associated with wind and wind-driven rain or sprays, a certain amount of residual moisture has been found to drip inside the garage as the door is opened. This moisture collects in the hinge space between the door sections and is held there under surface tension. The gravitational forces on the moisture in this location are insufficient to cause the moisture to drain away. However, once the sectional door is raised, the surface upon which the moisture has collected becomes tilted so that gravitational forces can overcome the surface tension resulting in water dripping inside the garage.
One commercially available sectional door has overcome this problem by extending the front facing of the upper door section downwardly across the space between the two door sections. This lip-type extension overlaps the upper, outer edge of the lower door section by only a centimeter or so but in a very close-fitting relationship. However, while this feature has solved the problems of water collecting in the joints between the door sections, it is my opinion that this type of construction is dangerous in that the lip acts as a very efficient guillotine for any fingers inadvertently placed in the gap that is created as the successive door sections traverse the curved portion of the track. Accordingly, while this particular door has solved the problem of water dripping inside the garage it has merely substituted a minor problem for a distinct danger, that is, severed fingers.
In view of the foregoing it would be an advancement in the art to provide an apparatus and method for inhibiting collected moisture from dripping from the joints in the sectional door as the sectional door is raised to its overhead position. Another advancement would be to provide a sectional door with a drip resistant tongue and groove system whereby collected moisture is inhibited from dripping inside the garage as the sectional door is opened. It would also be an advancement in the art to provide a tongue and groove system for a sectional door wherein the collected moisture is channeled to the edges of the sectional door as the sectional door is raised. Such a novel apparatus and method is disclosed and claimed herein.